Diagrams including pictograms increase stock-flow performance

Abstract

Stock-flow (SF) systems are omnipresent in our lives while difficult to understand. An example is the amount of CO2 in the atmosphere (stock) that changes in dependence of incoming CO2 (inflow) and outgoing CO2 (outflow). When participants are to deal with such tasks, they show poor performance. Despite several attempts to facilitate SF knowledge in participants, as far as we know, only one manipulation led to meaningfully increased SF performance: Changing the representation of the flows into pictograms. In the current study, we intend to modify these kind of diagrams so that they communicate SF information in a simple way. We tested whether the modified representation triggered basic SF understanding. Each participant worked on two tasks; one shown as line graph and one shown as diagram with pictograms. Getting the pictograms at first position led to strongly improved SF performance. A t-test revealed more correct solutions for pictograms than for line graph at first position. Again, the representation of the flows as pictograms led to better SF performance.